Now the vehicle ( truck , van , bus) is generally single-cooled. It needs to be added with Freon. Before adding, you must first check whether the pipeline leaks. You can pass the observation window.
The air conditioning condenser should be kept clean and ventilated, and designed to meet the wind, which is more conducive to refrigeration. The air conditioning system is equipped with a circulating ventilation filter and a refrigerant storage drying bottle, so it must be cleaned and replaced regularly during maintenance.